Arturo O. answered • 03/16/20

Experienced Physics Teacher for Physics Tutoring

(a)

a = F/m = -μmg/m = -μg

The deceleration is the absolute value of a.

|a| = μg = 0.8(9.8 m/s^{2}) = 7.84 m/s^{2}

(b)

Use the kinematic relation

v^{2} - v_{0}^{2} = 2ad

v = 0

v_{0} = 20 m/s

-v_{0}^{2} = 2ad

d = -v_{0}^{2} / (2a) = -(20)^{2} / [2(-7.84)] meters = 25.51 meters

Arturo O.

You are welcome, Benny.03/16/20

Benny W.

Thank you so much! I had trouble doing it and my teacher hasn’t bothered helping. So thank you so much!03/16/20